1. Field of the Invention
The invention is related to controlling borders between packet based networks, and in particular, to border control systems and methods.
2. Description of the Prior Art
Current Voice over Internet Protocol (VoIP) networks route voice communications using the IP format. Essentially, voice communications are converted into packets and transported through IP networks. In an example of a typical VoIP call from an on-net subscriber to an off-net destination, the subscriber to the VoIP network utilizes a phone program on a personal computer connected to the Internet. An application on the computer converts voice communications to packets and transmits the voice packets to the Internet. The packets are then routed to a gateway on a standard switched telephone network such as the public switched telephone network (PSTN). The voice packets are then routed through the PSTN to the destination for the call.
In an example of a typical VoIP call from an on-net subscriber to another on-net subscriber, both users utilize phone programs on their personal computers connected to the Internet. In this case, voice communications are converted to packets and transmitted over the Internet in accordance with routing instructions in the packet headers. The packets are routed in the same fashion as any other type of packet, such as a packet carrying email.
Problematically, VoIP calls suffer from low quality of surface and reliability. In both examples of the prior art, VoIP calls are either dumped to the nearest gateway and then routed on the PSTN, or the calls are routed over the Internet and suffer from low quality. In either case, intelligent routing decisions are not made to choose an optimal route, gateway, or otherwise.
One solution in the prior art to solve the persistent problems of low quality and reliability involves implementing dedicated VoIP networks. Unfortunately, stand alone dedicated VoIP networks are only able to provide high quality of service for a call between two subscribers to the dedicated VoIP service. If a call must reach the PSTN, dedicated VoIP networks do not possess intelligent gateway selection capabilities. Additionally, for a call that must transit between two competitive dedicated VoIP networks, intelligent border control capabilities do not exist.
Packet voice networks, such as VoIP networks, utilize border controllers to control traffic exchanged across various packet networks. Often times, numerous border controllers are employed between two packet networks. A typical border controller may consist of a firewall and an application server, for example. Packet switches typically perform call setup processing for calls across two packet networks, including choosing the particular border controller for a call.
For calls originating from a host packet network and destined for another competitive packet voice network, the host packet switch is responsible for choosing the border controller for the call. The host packet switch is also responsible for querying a corresponding packet switch in the destination packet network for the network address of the called party. The host packet switch is further responsible for alerting the destination switch of the identity of the chosen border controller. The host packet switch also notifies the calling device of the chosen border controller.
Problematically, requiring a host switch to interface with the destination switch inefficiently places processing burdens on the host switch that could be better directed towards other purposes. Requiring a host switch to choose a border controller also inefficiently burdens the switch. Furthermore, requiring host switches to communicate with several border controllers potentially opens security holes to the packet network of the host switch. Requiring the host switch to notify the destination switch of the chosen border controller creates additional potential security holes into the host packet network. Thus, improved operations between competitive networks is desired.